This invention relates to devices for the metering of postage and similar indicia and, more particularly, to a metering device including electronic circuitry for the encryption of the indicia to be printed.
Reference is hereby made to copending related patent applications assigned to the same assignee as this application; application of John Clark entitled "System Having A Character Generator For Printing Encrypted Messages", Ser. No. 515,073, filed on July 18, 1983, application of John Clark and Daniel Dlugos entitled "System For Printing Encrypted Messages With A Character Generator And Bar-Code Representation", Ser. No. 515,072, filed on July 18, 1983, and application of John Clark, Alton Eckert and David Warren entitled "System For Printing And Reading Of Encrypted Messages", Ser. No. 515,760, filed on July 21, 1983.
Postage meters find extensive use, both in the United States and abroad, for imprinting postage on objects to be mailed. The postage may be applied by a self-sticking label which is imprinted by a print head enclosed within the meter, the label then being placed in adhering contact on the letter, parcel or other object to be mailed. Alternatively, the postage may be printed directly on the outer wrapping of the object being mailed. The printing apparatus is also capable of printing a short message in addition to the amounts of the postage so that, if desired, the meter can be used for the imprinting of suitable indicia designating instructions and/or routing for transport by private carrier as well as by the mail. Furthermore, if desired, the meter may be utilized for the imprinting of yet other forms of labels, such as tax stamps, assuming that governmental approval for such tax stamps is obtained.
A serious problem which has been encountered in the use of imprinted postage is the fradulent adulteration of such postage labels whereby, in effect, the person adulterating the postage is stealing postage. A fraudulent label may enable someone to obtain postage, or in the case of a tax stamp, to avoid paying the tax.